Citation: Kabtani, J.; Militello, M.;
Ranque, S. Coniochaeta massiliensis sp.
nov. Isolated from a Clinical Sampl28.
J. Fungi 2022, 8, 999. https://doi.org/
10.3390/jof8100999
Academic Editor: Chi-Ching Tsang
Received: 16 June 2022
Accepted: 15 September 2022
Published: 23 September 2022
Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations.
Copyright: © 2022 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).
Fungi
Journal of
Article
Coniochaeta massiliensis sp. nov. Isolated from a
Clinical Sampl28
Jihane Kabtani
1
, Muriel Militello
1,2
and Stéphane Ranque
1,3,
*
1
Institut Hospitalo-Universitaire Méditerranée Infection, 19-21 Boulevard Jean Moulin, 13005 Marseille, France
2
Faculty of Medical and Paramedical Sciences, Aix-Marseille Université, AP-HM, IRD, SSA, MEPHI,
13005 Marseille, France
3
Department of Mycology and Parasitology, Aix-Marseille Université, AP-HM, IRD, SSA, VITROME,
13005 Marseille, France
* Correspondence: stephane.ranque@univ-amu.fr
Abstract: The genus Coniochaeta belongs to the class Ascomycota and the family Coniochaetaceae.
Some of the Coniochaeta species are plant and animal pathogens, while others are known to be
primarily involved in human diseases. In the last few decades, case reports of human infections
with Coniochaeta have increased, mainly in immunocompromised hosts. We have described and
characterised a new species in the genus Coniochaeta, here named Coniochaeta massiliensis (PMML0158),
which was isolated from a clinical sample. Species identification and thorough description were
based on apposite and reliable phylogenetic and phenotypic approaches. The phylogenetic methods
included multilocus phylogenetic analyses of four genomic regions: ITS (rRNA Internal Transcribed
Spacers 1 and 2), TEF-1α (Translation Elongation Factor-1alpha), B-tub2 (β-tubulin2), and D1/D2
domains (28S large subunit rRNA). The phenotypic characterisation consisted, first, of a physio-
logical analysis using both EDX (energy-dispersive X-ray spectroscopy) and Biolog
TM
advanced
phenotypic technology for fixing the chemical mapping and carbon-source oxidation/assimilation
profiles. Afterwards, morphological characteristics were highlighted by optical microscopy and scan-
ning electron microscopy. The in vitro antifungal susceptibility profile was characterised using the
E-test
TM
exponential gradient method. The molecular analysis revealed the genetic distance between
the novel species Coniochaeta massiliensis (PMML0158) and other known taxa, and the phenotypic
analysis confirmed its unique chemical and physiological profile when compared with all other
species of this genus.
Keywords: biolog phenotypic technology; Coniochaeta; energy-dispersive X-ray spectroscopy;
genotype; multilocus DNA sequencing; one new taxon; yeast
1. Introduction
Coniochaeta spp. are pleomorphic ascomycetous fungi belonging to the family Co-
niochaetaceae [1]. Some of these yeasts are also classified within dematiaceous fungi due to
the presence of melanin in cell walls, known for emitting dark pigments in culture, which
is perceived as a virulence factor [2]. Coniochaeta species are ubiquitously distributed in the
environment. They have been isolated from several natural substrates, including soil [3,4],
wood [5], plants [6], water [7], and food [8]. The previously given name Coniochaeta has been
retained for the Lecythophora genus, following the “one fungus, one name” nomenclature
change in January 2013. Therefore, all six species of the Lecythophora genus (L. decumbens,
L. fasciculata, L. hoffmannii, L. lignicola, L. luteoviridis, and L. mutabilis) were transferred to
the Coniochaeta genus [9,10]. C. hoffmannii and C. mutabilis are considered the most frequent
species of the Coniochaeta genus found in clinical samples. These yeasts are known to be
human pathogens, causing invasive fungal infections, occasionally with fatal outcomes, par-
ticularly in immunocompromised patients [11]. C. hoffmannii has been described as a plant
pathogen [12]. It has also been implicated in emerging human fungal infections, including
J. Fungi 2022, 8, 999. https://doi.org/10.3390/jof8100999 https://www.mdpi.com/journal/jof